Auto jack



F. S. BUNKER Oct. 28 1924.

AUTO JACK Original 'Filed Aug. 16 2 Sheets-Sheet i INVENTOR fizz/0% YBw/a?er" BY mwn IBm m Oct. .28 1924.

' INVENTOR 1 Fax} A53 Bazakr Patcntc ch28, 19241.

STATES FRANK S. BUNKER, F SPOKANE, WASHINGTON.

vA'IJ'EFJO JACK. I

Application filed August 16. 1921, Se1-la1 No. 492,717. Renewed September 15, 1984.

To all whom it may concern:

Be it known that I, FRANK S BUNKER, a citizen of the United States. residing at Spokane. in the county of Spokane and State of Washington, have invented new and useful Improvements in Auto Jacks, of which the following is a specification.

This invention relates to improvements in auto jacks and has to do more particu- 1 larly with an improved wheeled jack which is especially designed for use in garages and service stations in serving the public.

My invention includes lifting mechanism preferably ofthepressure type, which is mounted upon an improved support, one of the novel features of which is that the support has three points of engagement with the floor or other supporting surface.

My improved'support is specifically carried by hearing wheels forming two of such.

points of support, said support also includmg a frame journaled on or carried by said wheels and having an apex portion forming the remaining pointof support.

In the foregoing type of auto jack, it is a feature of my invention to mount the lifting mechanism preferably-rigidly on the frame, the rigid mounting being of such a character as slightly to yield sufiiciently to prevent telescoping portions of the lifting mechanism from binding, when under the heavier loads.

Itis also a feature of this invention to provide a novel form of handle whereby'the portable jack may be rolled into and out of operative positions, means being provided whereby the pressure necessary to operate the lifting mechanism may be conveyed to the latter, or exhausted therefrom, through the handle, whereby the handle may perform the dual function of a means for manipulating the jack and also causing its lifting mechanism to be energized.

A further object is to provide the im- 45. proved lifting mechanism with a mechanically extensible jack stem whereby the latter may be extensively or contractively ,adjusted to increase the range of operation of a iven sized jack. 1 y invention has many other features.

and objects which will be more fully described in connection with the accompanying drawings and which will be more parparticularly pointed out in and by the appended'claims.

Inthe drawingsz- Figure 1 is a view in side elevation of one form of my improved auto jack.

' Figure 2 is a view on line 22' of Fig- 111's 3, of the carriage portion of the jack, parts being in section and parts being in elevation.

Figure 3 is a plan view thereof.

Figure 4 is an enlarged sectional view of the manipulating end of the handle.

Figure 5. is a sectional view on line 5-5 of Figure 4.

Like characters of reference designate similar parts throughout the difierent figures ofthe drawings.

Reference will first be made to the carriage portion of the jack, such portion including bearing wheelsl, on which the jack is advanced. A substantially triangular frame '2 is journaled on an axle 3 which is fixed to thewheels 1. Said frame has a bight' or base portion4, parallel portions 5 and. ortions 6 which converge to an apex 7. t the apex 7, the'frame is provided with parallel-portions 8 to which a handle under load it is to all intents and purposes a rigid saddle. However, when the saddle is under heavy load, there is a suficient yield rmit the lifting mechanism to set itse f to support the load. This is one of the features of this inventiomthe function and advantage of which will be more ap parent when the lifting mechanism has been dacribed. 7

My improved lifting mechanism comprises a' pressure cylinder 12 which is referably provided with an integral upper cad 13 havm a suitable flange 14. A lower head 15 ving a suitable flange 16 is secured to the cylinder 12 by means such as bolts .17. The head rests upon the saddle 9 and the bolts 17 extend through the head 15 'andsaddle 9 thereby rigidly planting the cylindrical structure to the saddle. The head 15 is provided with an annular groove 18 into which the lower edge of the cylinder 12 seats. Said head is also provided with a pressure intake port 19 which opens to the bottom of cylinder 12 and which is connected at 20 with a pressure supply tube 21. A piston 22 is disposed in cylinder 12 and is e uipped with suitable packing as shown. iaid piston is provided with an .abutment 23 adapted to. engage a packing 24, mounted upon the head 15, whereby a 4 descending movement of the piston will be arrested. Said piston is provided with a sleeve 25 which projects through head 13 and has slidable engagement therewith at- 26, whereby the piston is guided. The bore 27 of said sleeve terminates at 28 and is provided on its upper end with a ratchet pawl projection 29, extending into the bore. A jack stem or bar 30 is loosely fitted in said sleeve and when-in a contracted adjustment, said bar rests on the bottom 28. The upper end of said bar has a jack seat 31 provided with protuberances 32, adapted to grip bottom portions of the auto to be elevated. One side of said bar 30jis provided with teeth 33, for engagement with pall 29. As shown in Figure 2, this extensible jack element is in a contracted adjustment. In Figure 1, the extensible ack is in a partially extended adjustment. By means of this feature, I am enabled to extend the range of this jack very materially without unduly enlar ing the same. Thus Iain able to get un er a very low car and hoist the same. or I am able to move the jack under a relatively h-igh car and lift the latter. In any position which the extensible feature may occupy, it is in rigid structural engagement with the piston sleeve and no movable parts of a-fastening nature are'necessary.

The desirability of having a very slightly yielding mounting for the lifting mechanism will now be clear, this being especially so when the mechanism is in an extended operative position. I

Attention will next be directed to my improved handle and to the various functions which it perform. p

The improved handle is designated at 34 the same being'in the form of a hollow' pipe of the general configuration shown in Figure 1. Thus it will be obvious that the' operator walking upright can gras "the pipe by the handle end35 and readi y advance or retract the jack to and from desired positions. The carriage end 36 of the pipe terminates in a connection 37 having an eye 38 extending between the frame members 8. A bolt 39 secures the handle in place and by reason of the engagement at 40, the cone tially rigid. The tube 21 is united with a nipple 41 and communicates with 37 thereby conveying the pressure medium to the bottom of cylinder 12.

, Tothe outer extremity of the handle end 35 is attached a fitting 42 into which a valved air service pipe connection 43 projects. The valve. stem is indicated at 44. Said fitting 42 is provided with a closure 45 having a valve seat projection 46. A valve closure 47 seats against the end of said projection and is provided with a stem 48 extending through said projection and having a button 49 on the outer end thereof. A spring 50 normally holds the closure .47 seated. Key grooves 51 may serve as channels to exhaust the .air from the handle.

Now when the jack is in position and ready to be operated to lift a portion of an auto, the air service hose is applied to 43.

Air under pressure is conveyed through the handle 34 and tube 21to the bottomjof piston 22 and the latter will be raised to the desired extent. 7 in part 43 will Trevent escape of air. and will hold the ja'cin its actuated position.

-When it .is desired to lower the auto, pres.

'sure is applied, manually, tothe button 49, in thedirection of the arrow shown in Figure 4, and the air may be exhausted from the The non-return valve 44,-

handle and the cylinder either as rapidly or l as gentl as desired. 1

It will be noted from Figures 1 and 2 that the frameof the carriage rtion is at an inclination to the horizonta when in a position of rest although the bottom of the saddle is substantially horizontal and the v except for such limitations 'as the claims may import.

I claim e I 1. An auto jack including a lifting mechanism, a three point support therefor comprising an axle and a pair of supportin wheels on said axle formin two points 0 support, a substantially triangular frame havmgits base end journalled on said axle and free from engagement with the floor,

and said frame .having an apex end for engagement with the floor and forming the remaining point of support, and a handle fixed to said apex end, whereby elevation of 2. An auto jack including lifting meehaand a three point support therefor insaid handle will lift said apex end 06 from 7 eluding a frame, and a slightly yieldable saddle rigidly hung on said frame and rigidly secured to said mechanism whereby the latter may slightly shift its position under the heavier loads.

3. An auto jack comprising a wheeled of said pipe 'for exhausting air from said cylinder to permit restoring movement of said piston.

4. An auto jack comprising a cylinder,.a piston in said 0 linder having a piston sleeve extending t rough and in uided engagement with one head ofsai cylinderhaving a fixed tooth, and a jack bar extension extensible in said sleeve and ha. teeth for engagement with said sleeve tooth to rigidly hold said bar in extensible positions.

5. .An auto jack substantially as described, having a hollow handle provided with a non-return valve for connection with an air service hose, and said handle having an exhaust valve for exhausting the air from said jack. c 6. An auto jack comprising a frame hav ing laterally spaced members,-a slight yieldable U-shaped saddle having its ends rigidly secured to said members and its bight spanning the space between said members below the anchored ends thereof, and lift ing mechanism rigidly secured to the bight of said saddle. I a

In testimony that. I claim the foregoing as my own, I hereby aflix my. signature. FRANK S. BUNKER. 

